The invention relates generally to microwave cooking apparatus and, more particularly, to an improved turntable mechanism for use in a microwave cooking oven.
It is known that in the cooking of certain foodstuffs in a microwave oven, hot spots develop in the foodstuff resulting in uneven cooking. In some cases, the result is overcooked areas, as compared to properly cooked portions of the foodstuff, or charred and carbonized areas of the foodstuff. Many instruction booklets accompanying microwave ovens do not discuss this problem directly, but do suggest rotating certain foodstuffs during cooking. The reason for the hot spots in the foodstuff is the inability to achieve a uniform distribution of microwaves in the oven cavity. Rotation of the foodstuff prevents overcooking of the foodstuff due to these localized hot spots.
Prior to applicant's invention, it has been known to incorporate a turntable and drive mechanism in a microwave oven structure. When cooking, foodstuffs are placed on the turntable and the turntable automatically rotates while the foodstuff is irradiated with microwave energy. In fact, such turntables are found in the prior art that include a rotatable table that may be detached from the drive mechanism and removed from the oven for cleaning and for use as a serving dish. However, the cost of building a drive mechanism and/or turntable into an oven structure as disclosed by the prior art is quite costly. Also, such a construction creates crevices or cramped areas in the oven cavity which are difficult to clean, thereby increasing the probability of debris collection and the creation of a generally unsanitary environment in the oven cavity.
In each of the prior art, built-in microwave oven turntables, the microwave oven floor or wall must be provided with a penetration for a drive shaft or the like. This increases the possibility of microwave leakage during operation of the oven and increases the cost of protection against such leakage.
Finally, the prior art does not provide a solution for the housewife with an existing microwave oven without a built-in turntable mechanism. Applicant is unaware of any conversion kit presently marketed for retrofitting an oven without a built-in turntable mechanism. Even if there were such conversion kits, these kits, if patterned after the prior art, would suffer from the same design and economic disadvantages. Thus, there is a need for an improved microwave oven turntable and more particularly, for a microwave oven turntable that is easily adapted for use in existing microwave ovens without a built-in turntable.